JPH0727662A - Method and device for detecting leaked can - Google Patents

Abstract

PURPOSE:To provide a device for detecting a leaked can quickly and accurately. CONSTITUTION:The device is provided with a first closed-end cylindrical can storage 4 with an inner-periphery surface along the outer periphery of a closed- end cylindrical can body K with an opening A in a lower end part and with an opening 2 for loading and unloading the can body K in the lower end part, a closed means 6 for forming a first space part 5 which is sealed between the can body K and the first can storage 4 by simultaneously closing the openings A and 2 while the bottom part of the can body K hits against the bottom part of the first can storage 4 by housing the can body K so that the can body K can be loaded freely from the opening 2 to the first can storage 4, a sealed second can storage 17 where a sealed second space part 16 in nearly the same shape as the first space part 5 is formed at a space with a pseudo can body 15 on storage after the pseudo can body 15 where air does not enter is housed, air supply pipes 23 and 24 for enclosing air with a specific pressure to the first and second space parts 5 and 16, and a differential sensor 29 for measuring the attenuation difference of pressure between the first space part 5 and the second space part 16 after enclosing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leaking can detecting method and a detecting device for detecting airtight leakage of a can body before the contents are hermetically filled.

[0002]

2. Description of the Related Art In the manufacturing process of beverage cans and the like, as shown in FIG. 5, a can body (a) before hermetically filling the contents, that is, an opening for filling the contents at the end on the mouth side Performing a leak inspection of a bottomed cylindrical can body equipped with b (for example, a leak inspection of the welded portion of the can body and the winding portion of the can lid on the bottom side),
The can body a that has passed the inspection is filled with the content, and a can lid (not shown) is wound around the opening b, thereby sealingly filling the content in the can body a, while failing. The can body a, that is, the leaking can is sorted and disposed of.

By the way, in order to detect a leaking can, the opening b is closed by a temporary lid d having a rubber packing c, and at the same time, an air hole e formed in the central portion of the temporary lid d is used to detect a can a.
Compressed air with a predetermined pressure is enclosed in the inside, and when the pressure decay after a predetermined time elapses more than a specified value, it is rejected and the above-mentioned disposal is performed.

In the above-described method for detecting a leaking can, compressed air is enclosed inside the can body. However, when the compressed air is enclosed in the can body a in this way, since the volume inside the can body a is large, a turbulent flow of air is generated in the can body a, which is very stable. take time. In this case, in order to measure the attenuation of the pressure in the can a after encapsulation, accurate measurement cannot be performed unless the air is stable, resulting in a problem that it takes a long time to detect a leak can.

Therefore, in order to solve such a problem, as shown in FIG. 6, a rod member f having a diameter slightly smaller than the diameter of the opening b of the can body a is inserted into the can body a so as to be inserted into the can body a. It is known that the inner volume is reduced to reduce the generation of air turbulence in the can body a and shorten the time during which the air stabilizes.

However, the can body a is usually subjected to so-called neck-in processing in which the opening b is formed to have a small diameter in order to reduce the cost by reducing the diameter of the can lid on the mouth side. Therefore, a small space can be formed by the rod member f described above at the end portion on the side of the mouthpiece, but a large space still exists in the other portions, and eventually the turbulent flow of air described above is good. However, there is a problem that it takes a long time to stabilize the air.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in order to solve such inconvenience, and provides a leak can detecting method and a leak can detecting device capable of accurately detecting a leak can in a short time. The purpose is to

[0008]

In order to achieve such an object, the method for detecting a leaking can according to the present invention is a bottomed cylindrical can body having an opening at one end where a can lid is wound. A bottomed cylindrical can container having an inner peripheral surface along the outer periphery of the can body and an opening at one end of which the can body is put in and taken out, the bottom part being the bottom part of the can container. Stored in a state of being abutted and in a state in which the can body and each opening of the can container are sealed so that a sealed space is formed between the can body and the can container. In this state, air having a predetermined pressure is enclosed in the space, and the leakage of the can body is detected by the attenuation of the pressure after the enclosure.

Further, the leaky can detecting device of the present invention has an inner peripheral surface along the outer periphery of a bottomed cylindrical can body having an opening for winding the can lid at one end. A bottomed cylindrical can container having an opening through which the can body is inserted and removed, and the can body is housed in the can container through the opening of the can container so that the can container can be freely taken in and out, Space sealed between the can body and the can container by simultaneously sealing the can body and each opening of the can container with the bottom of the can body abutting the bottom of the can container. A sealing means for forming a portion, an air enclosing means for enclosing air of a predetermined pressure in the space portion, and a pressure sensor for detecting attenuation of the pressure of the space portion after enclosing. Is.

Further, according to the method for detecting a leaky can of the present invention, a bottomed cylindrical can body having an opening at one end for winding the can lid is formed on the inner peripheral surface along the outer periphery of the can body. A bottomed tubular first can container having an opening through which the can body is inserted and removed at one end, with its bottom abutting against the bottom of the first can container, and Each of the can body and the first can container is accommodated in a hermetically sealed state so that a sealed first space is formed between the can body and the first can container. Further, a pseudo can body, into which air does not enter, is provided in a sealed second can container provided separately from the first can container, between the dummy can body and the second can container. The first space and the second space are accommodated so that a sealed second space having substantially the same shape as the first space is formed.
It is characterized in that air having a predetermined pressure is enclosed in the space portion, and the leakage of the can body is detected by a difference in pressure between the first space portion and the second space portion after the air is enclosed.

Further, the leaky can detecting device of the present invention has an inner peripheral surface along the outer periphery of a bottomed cylindrical can body having an opening for winding the can lid at one end. A bottomed cylindrical first can container having an opening through which the can body is taken in and out, and the can body is housed in the first can container through the opening of the first can container so that the can body can be freely taken in and out. In addition, at the time of accommodation, the opening of the can body and each opening of the first can container are simultaneously sealed in a state where the bottom part of the can body is abutted against the bottom part of the first can container to simultaneously seal the can body and the first can container. 1st sealed between 1 can container
A sealing means that forms a space and a pseudo can body that does not allow air to enter are housed, and a sealed second space part having substantially the same shape as the first space part is housed between the space and the pseudo can body. A sealed second can container provided separately from the formed first can container, and an air enclosing means for enclosing air of a predetermined pressure in the first space part and the second space part, A differential pressure sensor for detecting a difference in pressure between the first space portion and the second space portion after encapsulation is provided.

Further, the leaky can detecting device of the present invention is characterized in that the second can container is connected to the other end of the first can container.

[0013]

According to the present invention, a bottomed cylindrical can body having an opening for winding the can lid at one end has an inner peripheral surface along the outer periphery of the can body and has a can at one end. A bottomed cylindrical can container having an opening through which a body is put in and out, and a state in which the bottom part is abutted against the bottom part of the can container and is sealed between the can bodies. Each opening of the can body and the can housing body is housed in a sealed state so that a space is formed. For this reason,
A space having a small volume can be easily formed between the outer surface of the can body and the inner surface of the can housing body. Therefore, when air having a predetermined pressure is enclosed in the space, the air can be blown for a short time. Can be stabilized.

In addition, the above-mentioned can body is formed into a bottomed cylindrical first can housing body having an inner peripheral surface along the outer periphery of the can body and having an opening at one end through which the can body is taken in and out. The can body and the first can housing so that the sealed first space portion is formed between the can body and the first can housing body with the bottom portion abutting the bottom of the first can housing body. A pseudo-can body that encloses each opening of the body in a sealed manner and is air impermeable
In the sealed second can container provided separately from the can container, a sealed second space part having substantially the same shape as the first space part is formed between the pseudo can body and the second can container. As described above, in this state, air having a predetermined pressure is enclosed in the first space portion and the second space portion, and the difference in pressure between the first space portion and the second space portion after the enclosure is measured. In this case, the variation in the measured values can be reduced as compared with the case where the pressures in the first space portion and the second space portion are measured separately, and therefore the first
The significant difference between the space portion and the second space portion can be increased.

Furthermore, when the second can container is connected to the other end of the first can container, the structure of the device can be simplified and the installation space can be reduced.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a cross-sectional view of a main part of a leaky can detecting device according to an embodiment of the present invention, and FIG. 2 is an explanatory cross-sectional view for explaining a leaky can detecting method.

First, the can body K to be detected will be described. As shown in FIG. 1, the can body K has a can body portion D formed into a cylindrical shape by welding and a bottom portion of the can body portion D. It is formed into a cylindrical shape with a bottom by a can lid B wound around the end on the side (upper end), and the end on the side of the mouth (lower end) is an opening filled with contents. Part A is formed. Further, the end portion on the side of the drinking mouth is formed into a small diameter by performing the neck-in processing described above.

Next, a leak can detecting device 1 according to an embodiment of the present invention will be described with reference to FIGS.

The detection device 1 has an inner peripheral surface along the outer periphery of the can body K, and has an opening 2 at the lower end thereof through which the can body K is taken in and out, the upper end of which is defined by a bottom lid 3. It is provided with a closed bottomed cylindrical first can housing 4. Below the first can container 4, the can body K is accommodated in the first can container 4 through the opening 2 of the first can container 4 so that it can be freely taken in and out, and at the time of housing, the bottom part of the can body K is placed. The can body K and the first can housing body 4 are sealed at the same time while the can body K and the respective opening portions A and 2 of the first can housing body 3 are sealed at the same time while being abutted against the bottom lid 3 of the first can housing body 4. A sealing means 6 is arranged which forms a sealed first space 5 therebetween.

The sealing means 6 has a tubular portion 7 arranged concentrically with the first can housing body 4, and the opening 2 of the first can housing body 4 is provided at the upper end of the tubular portion 7. The first sealing portion 8 in the shape of a short cylinder that seals is fixedly fitted. A rod-shaped portion 9 is movably inserted in the inside of the tubular portion 7, and a second columnar closed portion having a short column shape for sealing the opening A of the can body K is provided at an upper end portion of the rod-shaped portion 9. 10 are connected while being accommodated in the inner peripheral portion of the upper end of the first sealing portion 8. In the housed state, the upper end surface of the second hermetically sealed portion 10 is arranged slightly below that of the first hermetically sealed portion 8.

A supply passage 11 for supplying the can body K to the upper side of the second sealing portion 10 is arranged on the left side of the first sealing portion 8 at the same level as the upper end surface of the first sealing portion 8. There is. On the right side of the first sealing portion 8, a holding member 12 that sucks and holds the can body K supplied from the supply path 11 to above the second sealing portion 10 by a suction nozzle 12a is arranged so as to be movable back and forth. In the held state, as described above, since the upper end surface of the second hermetically sealed portion 10 is arranged slightly below that of the first hermetically sealed portion 8, the lower end of the can body K has the second hermetically sealed portion 10. The upper end of the can body K is prevented from being damaged by the second sealing portion 10 at the time of supply.
It should be noted that the holding member 12 is retracted to release the holding of the can body K when the sealing means 6 to be described later is raised.

In the sealing means 6, the first and second sealing parts 8 and 10 are simultaneously moved up and down by a driving means (not shown), and the first sealing part 8 of the first can container 4 is moved up. At the same time as the O-ring 13 provided on the lower end face is pressed to seal the opening 2 of the first can housing 4, the upper end face of the second sealing portion 10 closes the opening A of the can K to close the opening A. The opening A is sealed by the O-ring 14 provided between the outer peripheral surface of the second sealing portion 10 and the inner peripheral surface of the first sealing portion 8. In the state where the openings 2 and A are closed, the bottom of the can body K is in contact with the bottom lid 3 of the first can container 4, and the outer peripheral surface of the can body K and the first can container 4 are in contact with each other. A sealed first space 5 having a small volume is formed between the inner space and the inner peripheral surface.

Further, the bottom lid 3 of the first can container 4 accommodates a pseudo can body 15 into which air does not enter, and the space between the pseudo can body 15 and the pseudo can body 15 is substantially the same as that of the first space 5. The second can housing 17 in which the sealed second space 16 is formed is connected.

The pseudo can body 15 has substantially the same shape as the can body K, and has a pseudo can body portion 18 extending upward from the bottom lid 3 of the first can housing body 4, and an upper end of the pseudo can body portion 18. And a plug 19 for sealing the opening of the part. Second can container 1
7 has an inner peripheral surface along the outer periphery of the pseudo can body 15, and has an upper end portion closed by a bottom lid 20 to form a bottomed cylindrical shape. After being inserted, the lower end portion is connected to the bottom lid 3 of the first can housing body 4 by bolting. In this way, the second
By connecting the canisters 17, the structure of the device 1 can be simplified and the installation space can be reduced.

In the figure, reference numerals 21 and 22 denote the second
This is an O-ring that secures the sealed state of the can housing 17, and by thus sealing the second can housing 17, the outer peripheral surface of the pseudo can body 15 and the inner peripheral surface of the second can housing 17 are closed. A sealed second space portion 16 having substantially the same shape as the first space portion 5 is formed between and. Note that reference numerals 22a and 22b
Is a plurality of air passage grooves formed in the circumferential direction on the lower surfaces of the stopper 19 and the bottom cover 3, respectively. These air passage grooves 22
a and 22b are a space between the stopper 19 and the bottom of the dummy can 15, and a space between the bottom lid 3 and the bottom of the can K when the first and second can housings 4 and 17 are filled with air. It forms a passage for the air to flow into.

In the first space 5 and the second space 16 described above, the air supply pipes 23, which are connected to the outer peripheral surfaces of the right side portions of the first can housing 4 and the second can housing 17, respectively.
24 to a predetermined pressure (in this embodiment, 0.8 to 1.0 k
g / cm ² ) of air is enclosed. Air supply pipe 23,2
4, solenoid valves 25 and 26 are interposed in the middle of the solenoid valve 4, and after joining the upstream side of the solenoid valves 25 and 26, they are connected to an air supply device (not shown). The solenoid valve 2
5, 26 are closed by a control means (not shown) after supplying a predetermined amount of compressed air to the first and second spaces 5, 16.

Further, the first can container 4 and the second can container 1
One end of each of the pipes 27 and 38 communicating with the first space portion 5 and the second space portion 16 is connected to each left side outer peripheral surface of 7, and the other end of each of the pipes 27 and 28 is connected to the differential pressure sensor 29. It is connected. The differential pressure sensor 29 is for measuring the difference in attenuation of pressure in the first space portion 5 and the second space portion 16 in which air is sealed after a predetermined time has elapsed, and the difference in pressure is not less than a specified value. In this case, the welded portion of the can body D of the can body K or the winding portion of the can lid B is detected as a leaking can. In addition, after detecting the leaking can,
The exhaust valves (not shown) provided in the two-can housings 4 and 17 are opened to release the air in the first and second spaces 5 and 16 to the outside, and the sealing means 6 descends and leaks. The can is discharged.

In the detection device 1 having the above structure, the can body K
The first can housing body 4 having an inner peripheral surface along the outer circumference of the can body K, with its bottom part abutting the bottom part of the first can housing body 4, and The can body K and the openings A and 2 of the first can housing body 4 are housed in a hermetically sealed manner so that a sealed first space 5 is formed between the can body 4 and the can housing body 4. Therefore, a space having a small volume can be easily formed between the outer surface of the can body K and the inner surface of the first can housing body 4. Therefore, when the air having a predetermined pressure is enclosed in the first space 5, the air can be stabilized in a short time, and the attenuation of the pressure after the enclosure can be measured accurately in a short time.

In addition, a sealed second space portion 16 having substantially the same shape as the first space portion 5 is formed between the pseudo can body 15 and the pseudo can body 15 in the first can housing body 4. The second can housing 17 is connected, and the first space 5 and the second space 16 are filled with air of a predetermined pressure, and the first space after a predetermined time elapses.
Since the pressure difference between the space 5 and the second space 16 is measured by the differential pressure sensor 29, the first space 5 and the second space
Compared to the case where the pressure attenuation of the space 16 is measured separately, it is possible to reduce the variation in the measured values.
The significant difference between the space portion 5 and the second space portion 16 can be increased.

Here, the effectiveness of the differential pressure sensor 29 will be described in more detail with reference to FIGS. 3 and 4. In FIG. 3, the first can container 4 and the second can container 1 are replaced by the differential pressure sensor 29.
7 shows a detection device 32 having the same configuration as the detection device 1 except that pressure sensors 30 and 31 that communicate with the first space portion 5 and the second space portion 16 are provided on the outer peripheral surface of each left side portion of 7. FIG. 4 shows the detection device 1 and the detection device 32,
After air is filled in the space 5 and the second space 16, 460 m
The result of subtracting the measured value after 560 msec from the measured value after sec is shown.

As is apparent from FIG. 4, the differential pressure sensor 29
Compared with the detection device 32 that uses the pressure sensors 30 and 31, the detection device 1 that uses 1 is significantly smaller in the dispersion of measured values, and the significant difference is 166 g / mm ² (431-27).
5 = 166) was also large. As the can body K, a can body having a hole of 0.06 mm was used for the first can container 4.

The present invention is not limited to the above embodiments, but can be modified as appropriate without departing from the gist of the present invention. For example, in the above embodiment, the differential pressure sensor 2
9 is used to measure the pressure difference between the first space 5 and the second space 16, but instead of this, the pressure sensors 30 and 31 are used as in the detection device 32 described above. It is also possible to separately measure the attenuation of the pressure in the first space portion 5 and the pressure in the second space portion 16 and obtain the difference in the attenuation between them.

In the above embodiment, the leak can is detected by measuring the differential pressure between the first space portion 5 and the second space portion 16, but instead of this, one pressure sensor (not shown) is used. It is also possible to detect the leak can by measuring the pressure attenuation only in the first space section 5). In this case, as a result, the pseudo can body 15 and the second can container 17 become unnecessary.

[0034]

As is apparent from the above description, according to the present invention, a space having a small volume can be easily formed between the outer surface of the can body and the inner surface of the can housing body. When air having a predetermined pressure is enclosed in the space, the air can be stabilized in a short time, and the attenuation of the pressure after the enclosure can be accurately measured in a short time.

Further, the second can in which the sealed second space portion having substantially the same shape as the first space portion 1 is formed between the pseudo can body when the pseudo can body is accommodated in the first can container. Connect the containers,
After enclosing air of a predetermined pressure in the first space portion and the second space portion,
When the pressure difference between the first space portion and the second space portion after a predetermined time has elapsed is measured by a differential pressure sensor, the pressure attenuation between the first space portion and the second space portion is measured separately. It is possible to reduce the dispersion of measured values compared to
Therefore, the significant difference between the first space portion and the second space portion can be increased.

Furthermore, when the second can container is connected to the other end of the first can container, the structure of the device can be simplified and the installation space can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts of a leak can detecting device according to an embodiment of the present invention.

FIG. 2 is an explanatory cross-sectional view of essential parts for explaining a method for detecting a leaking can.

FIG. 3 is an explanatory cross-sectional view of essential parts for explaining the effectiveness of the differential pressure sensor.

FIG. 4 is an explanatory diagram for explaining a comparison between a differential pressure sensor and a pressure sensor.

FIG. 5 is an explanatory sectional view for explaining a conventional method for detecting a leak can.

FIG. 6 is an explanatory cross-sectional view for explaining another conventional method for detecting a leak can.

[Explanation of symbols]

1 ... Leakage can detecting device, K ... Can body, A, 2 ... Opening part, 4
... first can container, 5 ... first space portion, 6 ... sealing means, 15
... pseudo can body, 16 ... second space part, 17 ... second can container,
23, 24 ... Air supply pipes, 25, 26 ... Solenoid valves, 29 ...
Differential pressure sensor

Claims (5)

[Claims] 1. A bottomed cylindrical can body having an opening for winding a can lid at one end, wherein the can body has an inner peripheral surface extending along the outer periphery of the can body. In a bottomed cylindrical can container having an opening for inserting and withdrawing, the bottom part is abutted against the bottom part of the can container, and is sealed between the can body and the can container. The can body and each opening of the can container are housed in a sealed manner so that a space is formed, and in this state, air of a predetermined pressure is sealed in the space, and the pressure after sealing is sealed. A method for detecting a leaking can, comprising detecting the leakage of the can body by attenuating the can. 2. An opening portion having an inner peripheral surface along the outer circumference of a bottomed cylindrical can body having an opening portion at one end for winding the can lid, and an opening portion into and out of the can body at one end portion. With a bottomed cylindrical can container, and the can body is accommodated in the can container through the opening of the can container so as to be freely inserted and removed, and at the time of housing the bottom part of the can container of the can container. Sealing means for simultaneously sealing each opening of the can body and the can container while abutting against the bottom to form a sealed space between the can body and the can container, and the space. An apparatus for detecting a leak can, comprising: an air enclosing means for enclosing air of a predetermined pressure in a portion thereof, and a pressure sensor for detecting attenuation of the pressure of the space portion after enclosing. 3. A bottomed tubular can body having an opening for winding a can lid at one end, wherein the can body has an inner peripheral surface along the outer periphery of the can body. In a bottomed tubular first can container having an opening to be taken in and out, with the bottom abutting against the bottom of the first can container, and the can body and the first can container. And a pseudo can body in which each opening of the can body and the first can housing body is housed in a hermetically sealed manner so that a sealed first space portion is formed between them, and further air does not enter. However, in a sealed second can container provided separately from the first can container, a seal having substantially the same shape as the first space is provided between the pseudo can body and the second can container. The second space portion is housed so as to be formed, and in this state, air having a predetermined pressure is sealed in the first space portion and the second space portion, and the first space portion and the second space portion are sealed. Detection method for leak cans and detects a leakage of the can body by a difference in pressure between the spatial portion second space portion. 4. An opening portion having an inner peripheral surface along the outer periphery of a bottomed tubular can body having an opening portion at one end for winding the can lid, and at which the can body is taken in and out. First cylinder with a bottom
A can container and the can body are housed in the first can container so as to be freely inserted into and removed from the first can container through the opening of the first can container, and at the time of housing, the bottom of the can container is set to the bottom of the first can container. A sealing means for simultaneously sealing the openings of the can body and the first can housing body in a state of abutting to form a sealed first space between the can body and the first can housing body. And a first can in which a pseudo can body, into which air does not enter, is housed, and a sealed second space part having substantially the same shape as the first space part is formed between the pseudo can body and the pseudo can body when housed. A closed second can container provided separately from the container, an air enclosing means for enclosing air of a predetermined pressure in the first space and the second space, and the first space after encapsulation And a differential pressure sensor for detecting a pressure difference between the second space portion and the second space portion. Of the detection device. 5. The leak can detecting device according to claim 4, wherein the second can container is connected to the other end of the first can container.